FI97389C - Process for the preparation of morpholinyl derivatives of doxorubicin, diiodo intermediate used in the process and process for its preparation - Google Patents

Abstract

Morpholinyl derivatives of doxorubicin having the general formula A: <CHEM> wherein X represents a linear or branched C1-c6 alkyl group or a benzyl group -CH2C6H5, and having (S) or (R) configuration at carbon atom C-2" of the morpholino ring, are antitumor agents.

Description

97389

Process for the preparation of morpholinyl derivatives of doxorubicin, diiodo intermediate used in the process and process for its preparation

The invention relates to a process for the preparation of anthracycline glycosides, to a diiodo intermediate used in the process and to a process for its preparation.

The invention provides a process for the preparation of novel anthracycline glycosides of general formula A, wherein the 31-nitrogen atom is attached to the 2-alkoxy-4-morpholinyl ring: OCH, O HO i J 0

"TV

h. wherein X represents a straight or branched C 1 -C 6 alkyl group or a benzyl residue -CH 2 C 8 H 5 and has the (S) - or (R) configuration at the 2 "carbon atom, and for the preparation of pharmaceutically acceptable salts thereof. The most preferred salt is the hydrochloride salt.

Morpholino-anthracyclines are well known compounds with promising antitumor activity in experimental mouse tumors (see E. W. Acton, "Bioactive Molecules", 55-101, Part 6, published by J. W. Lown, Elveiser 1988). Of these, 2-methoxy-4-morpholinyl anthracyclines (X = OCH 3) are already disclosed in our patent US-A-4,672,057. These ; compounds are prepared by a reductive alkylation method

• I

using a chiral dialdehyde. On the other hand, in this 2 97389 invention, substituted morpholinyl rings are prepared by bis-alkylating the 3'-amino group of anthracyclines with novel chiral 1,5-diiodo-2-alkoxy or benzyloxy derivatives, the process for the preparation of which is within the scope of the invention.

Preferred anthracycline glycosides of general formula A are: Al: 3'-deamino-3 '- (2 "- (S) -benzyloxy-4" -morpholinyl) -doxorubicin (X = CH 2 C 6 H 5), A 2: 3'-deamino- 3 '- (2 "- (S) -ethoxy-4" -morpholinyl) -doxorubicin (X = C2H5), A3: 31-deamino-3' - (2 "- (R) -isopropyloxy-4" -morpholinyl) -doxorubicin (X = CH (CH3) 2), A4: 3'-deamino-3 '- (2 "- (S) -methoxy-4" -morpholinyl) -doxorubicin (X = CH3) and A5: 3'- deamino-3 '- (2 "- (R) -methoxy-4" -morpholinyl) -doxorubicin (X = CH3) and their hydrochloride salts. The compounds may have the (S) or (R) configuration at the C-2 "carbon atom of the morpholino ring.

The novel according to the method of the invention, i.e. Anthracycline glycoside antibiotics of general formula A are prepared by forming a substituted morpholinyl ring on the C-3 'atom of the sugar moiety of antitumor anthracycline glycoside doxorubicin (B) <WH, Y h4 £' CHr? ------ vfrnu 1.

The present invention thus provides a process for the preparation of an anthracycline glycoside of formula A or a pharmaceutically acceptable one thereof.

II

3 97389 for the preparation of an acceptable acid addition salt, wherein:

(i) doxorubicin or an acid addition salt thereof, for example the hydrochloride salt, is reacted with a compound of general formula C

XX.

c) wherein the residue X has the meaning defined above, and (ii) if desired, converting the anthracycline glycoside of formula A thus obtained into a pharmaceutically acceptable acid addition salt thereof.

Alkylation of the C-31 amino group of doxorubicin or the doxorubicin salt is typically performed in step (i) in a polar aprotic solvent and in the presence of a dry organic base such as triethylamine. The reaction is generally carried out at room temperature for 8 to 24 hours. The carbon atom C-2, which contains an -OX group in the di-di compound, may have the (S) or (R) configuration.

In a preferred embodiment, doxorubicin or its hydrochloride dissolved in a polar aprotic solvent is reacted with a diiodo compound of general formula C at room temperature and in the presence of a dry organic base to give the corresponding morpholinyldoxorubicin derivative of formula A, on a silica gel column using a methylene chloride-methanol (97: 5, v / v) elution system and isolated as the hydrochloride by treatment with methanolic anhydrous hydrogen chloride. Thus, according to the process of the present invention, there is provided pure 2 "- (R) - [(C 1 -C 6 alkoxy- or benzyloxy] -anthracycline glycoside of formula A or a salt thereof or pure 2" - (S) - [ (C 1 -C 6) alkoxy or benzyloxy] anthracycline glycoside or a salt thereof.

• · 97389 4

The invention also provides a process for the preparation of optically pure diiodo compounds C using as starting materials sugar precursors, such as a compound of general formula S formed from L-arabinose 5 wherein residue X has the meaning defined above. In this method: (a) subjecting to periodate oxidation a compound of formula S1 in which residue X has the meaning defined above, (b) reducing the dialdehyde derivative of formula D1 ° Qox thus obtained in which residue X has the meaning defined above, (c) sulfonating the compound thus obtained. a dihydroxy derivative of the formula E1 HO—- 'VOX HO—' wherein the residue X has the meaning defined above, and (d) iodination of the sulfonated derivative thus obtained.

5 97389

For the preparation of diiodo compounds C, the 1-substituted sugars S1 prepared in "Methods on Carbohydrate Chemistry", Acad. Press., Vol. 1 (1962), is first converted to dialdehyde derivatives D *. Generally, D- or L-arabinose is used as the starting material. This is reacted with the alcohol X-OH to form a compound of formula S1. Di-aldehyde derivatives can be prepared using periodate oxidation in water, then reduced to 1,5-dihydroxy-2-alkoxy or benzyloxy-3-oxapentane E1 using reducing agents such as sodium borohydride or sodium cyanoborohydride at pH 6. 5 in a mixture of water and methanol.

The dihydro compounds E1 formed are sulfonated at 1- and 5-hydroxyl groups, conventionally using p-toluenesulfonyl chloride in pyridine at 4 ° C to give sulfonyl esters of formula F, from which diiodo derivatives C are obtained by treatment with sodium or potassium iodine in an aprotic solvent such as aprotic solvent. at 85oC for 1-2 days. The order of these reactions does not affect the chirality at the C-2 atom of the diiodo compounds C, which is the same as that of the starting sugars S.

A preferred embodiment of the process according to the invention is shown by the following reaction scheme: 6 97389

Reaction scheme ^ - ^ .- (0.]

i ° n SL

L-arabinose -α-a. - ~ α, £. Σ ε_ 6ch, O HÖ £ XX, ‘

The compounds of this invention may be used in pharmaceutical compositions comprising a pharmaceutically acceptable carrier or diluent and an anthracycline glycoside of formula A or a pharmaceutically acceptable acid addition salt thereof as an active ingredient. Conventional carriers or diluents may be used. The composition may be formulated and administered, for example, intravenously, in a conventional manner.

The anthracycline glycosides of formula A and their pharmaceutically acceptable acid addition salts are antitumor agents. They can be used to treat a patient with a tumor by administering a therapeutically effective amount of these compounds. The compounds can be used to inhibit tumor growth and are non-toxic at therapeutic doses.

The following examples illustrate the invention.

Example 1 Preparation of 1,5-di- (p-toluenesulfonyl) oxy-2 (S) -benzyloxy-3-oxapentane (FJL) L-arabinose (3 g, 0.022 mol) and benzyl alcohol (15 ml) were heated with stirring to Dowex 50 wx in the presence of 2 (2 g, acid form). After 4 hours, the mixture was cooled and filtered. The solvent was removed under reduced pressure and 1-benzyl-3-L-arabinopyranoside (SI, 3.5 g) was taken up in acetone. TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol / water (120/20/2 v / v), Rf = 0.47. [α] D = + 215 ° (c = 1% water).

1-Benzyl-O-L-arabinopyranoside (SI, 3.48 g, 0.0145 mol) was dissolved in water (100 mL) and treated with sodium periodate (5.6 g, 0.026 mol) at 0 ° C for 2 hours. Barium chloride was then added and the mixture was adjusted to pH 8 97389 with 7 barium carbonate, filtered and washed with water. The aqueous solution was concentrated under reduced pressure to a syrup and extracted with acetonitrile (50 mL). The organic phase was diluted with a mixture of methanol (20 ml) and water (10 ml) and treated with sodium cyanoborohydride (0.3 g) dissolved in water (5 ml). After 15 minutes, the mixture was adjusted to pH 7 by the addition of Dowex 50 W x 2 and filtered. The solvents were removed under reduced pressure to give 1,5-dihydroxy-2 (S) -benzyloxy-3-oxapentane (EI, 2.6 g, 85% yield). TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol (10/1 v / v), Rf = 0.28. Compound E1 (2.6 g) was dissolved in dry pyridine and p-toluenesulfonyl chloride (6.67 g) was added. The mixture was kept at 0 ° C overnight, then poured into ice-water and extracted with methylene chloride. The organic phase was washed with water, separated, dried over anhydrous sodium sulfate and filtered. The solvent was removed under reduced pressure to give 1,5-di (p-toluenesulfonyl) oxy-2 (S) -benzyloxy-3-oxapentane (F1, 4.3 g, 68% yield).

TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / acetone (98/2, v / v), Rf = 0.55.

1 H-NMR (CDCl 3, 400 MHz) δ: 2.42 (S, 6H, two CH 2 Cl 2); 3.65 - 3.69 (2 dt, J = 4.7, 11.7 Hz, 2H, TsOCH 2 CH 2 O); 3.94 (2 dd, J = 5.3, 10.5 Hz, 2H, OCH-CH 2 -OTS); 4.08 (t, J = 4.7 Hz, 2H, Ts-O-CH 2 CH 2 -O); 4.46, 4.56 (2 d, J = 11.7 Hz, 2H, OCH 2 -Ph); 4.72 (t, J = 5.3 Hz, 1H, O-CH-CH2-OTs); 7.2-7.8 (m, 13H, aromatics).

Example 2 Preparation of 1,5-diiodo-2 (S) -benzyloxy-3-oxapentane (Cl)

Compound F1 (4.3 g, 8.3 mmol) prepared as described in Example 1 was dissolved in methylethyl ketone (97 mL) and then sodium iodide (7.4 g, 49 mmol) was added. The mixture was kept at 95 ° C for 24 hours. The solvent was then removed under reduced pressure, and the residue was extracted with n-hexane. The organic phase was concentrated to a syrup to give the title compound Cl (3.5 g, 90% yield). TLC, Kieselgel Plate F254 (Merck), elution system n-hexane / ethyl acetate (10 / 0.5 v / v), Rf = 0.34.

1 H-NMR (CDCl 3, 400 MHz) δ: 3.27 (t, J = 6.8 Hz, 2H, J-CH 2 CH 2 -O); 3.30 (d, J = 5.5 Hz, 2H, O-CH-CH 2 -J); 3.84 (m, 2H, J-CH 2 CH 2 -O); 4.63, 4.74 (2 d, J = 11.7 Hz, 2H, Q-CH 2 Ph); 4.81 (t, J = 5.5 Hz, 1H, O-CH-CH 2 -J); 7.3-7.5 (m, 5H, aromatics).

Example 3 Preparation of 3'-deamino-3 '- [2 (S) -benzyloxy-4-morpholinyl] -doxo-rubicin (AI)

To a solution of doxorubicin hydrochloride (0.5 g, 0.86 mmol) in dry dimethylformamide (20 mL) was added 1,5-diiodo-2 (S) -benzyloxy-3-oxapentane (Cl, 3.5 g, 7.54 mmol) and dry triethylamine (3.6 mL, 2.6 mmol). The mixture was kept at room temperature for 36 hours, then poured into water and extracted with methylene chloride. After completion of the standard final steps, the crude product was purified on a silica column using a mixture of methylene chloride and methanol (97/5, v / v) as an elution system, followed by treatment with methanolic anhydrous hydrogen chloride to give the title compound A1 (0.3 g, yield 46%) as the hydrochloride salt. TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol (10/1 v / v), Rf = 0.6. FD-MS: m / e 756 (M &lt; + &gt;).

1 H-NMR of the free base (CDCl 3, 200 MHz) δ: 1.37 (d, J = 6.6 Hz, 3H, 5'-CH 3); 1.76 (m, 2H, 2'-δ); 2.14 (dd, J = 3.9, 97389 14.8 Hz, 1H, 8ax-H); 2.2 - 2.7 (m, 6H, CH 2 -N-CH 2, 8e <3-H, 31-H); 3.00 (d, J = 18.8 Hz, 1H, 10ax-H); 3.55, 4.00 (2 m, 2H, O-CH 2 CH 2 N); 3.68 (s, 1H, 4'-H); 3.94 (q, J = 6.6 Hz, 1H, 5'-H); 4.08 (S, 3H, OCH 3); 4.51, 4.77 (2 d, J = 12.1 Hz, 2H, OCH 2 Ph); 4.65 (dd, J = 2.6, 4.0 Hz, 1H, OO (OCH 2 Ph) CH 2 N); 4.71 (s, 1H, COCH 2 OH); 5.28 (dd, J = 2.4, 3.8 Hz, 1H, 7-H); 5.54 (m, 1H, 1'-H); 7.2-8.1 (m, 8H, aromatic Hs); 13.22 (s, 1H, 11-OH); 13.95 (s, 1H, 6-OH).

Example 4 Preparation of 1,5-diiodo-2 (S) -ethoxy-3-oxa-pentane (C2)%

The title compound C2 was prepared starting from L-arabinose (3 g) and following the reaction procedure of Examples 1 and 2.

1-ethyl-p-L-arabinopyranoside (S2), [α] D = + 233.5 ° (c = 1% water). 1,5-Dihydroxy-2 (S) -ethoxy-3-oxa-pentane (E2): TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol (10/1 v / v), Rf = 0.33.

1,5-di (p-toluenesulfonyl) oxy-2 (S) -ethoxy-3-oxa-pentane (F2): TLC, Kieselgel Plate F2g4 (Merck), elution system methylene chloride / acetone (98/2, v / v) , Rf = 0.56.

1 H-NMR (CDCl 3, 200 MHz) δ: 1.11 (t, J = 7.0 Hz, 3H, OCH 2 CH 3); 2.43 (s, 6H, 2 CH 3 -TS); 3.44, 3.58 (2 dq, J = 7.0, 9.4 Hz, 2H, OCH 2 CH 3); 3.68 (m, 2H, O-CH2-CH2-OTs); 3.89 (d, J = 5.4, 2H, o-CH-CH 2 -OTS); 4.10 (t, J = 4.8 Hz, 2H, OCH 2 -CH 2 O 5); 4.61 (t, J = 5.4 Hz, 1H, O-CH-CH 2 O 5); 7.3-7.8 (m, 8H, aromatic Hs).

1,5-diiodo-2 (S) -ethoxy-3-oxa-pentane (C2): TLC, Kieselgel Plate F254 (Merck), elution system n-hexane / ethyl acetate (10 / 0.5 v / v), Rf = 0 , 37.

Δ 11 97389 1 H-NMR (CDCl 3, 200 MHz) δ: 1.24 (t, 7.0 Hz, 3H, OCH 2 CH 3); 3.23 (d, J = 5.6 Hz, 2H, J-CH 2 CH-O); 3.27 (t, J = 6.8 Hz, 2H, J-CH 2 CH 2 -O); 3.58, 3.77 (2 dq, J = 7.0, 9.3 Hz, 2H, OOT2CH3); 3.78, 3.87 (2 dt, J = 6.8, 10.6 Hz, 2H, J-CH 2 CH 2 -O); 4.70 (t, J = 5.6 Hz, 1H, O-CH-CH 2 -J).

Example 5 Preparation of 3'-deamino-3 '- [2 (S) -ethoxy-4-morpholinyl] -doxorubicin (A2)

Doxorubicin hydrochloride (0.5 g) was reacted with C2 (3 g) following the procedure of Example 3 to give the title compound A2 (0.28 g) as the hydrochloride salt. TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol (10/1 v / v),

Rf = 0.58. FD-MS: m / e 694 (M &lt; + &gt;).

1 H-NMR of the free base (CDCl 3, 200 MHz) δ: 1.16 (t, J = 7.0 Hz, 3H, OCH 2 CH 3); 1.36 (d, J = 6.4 Hz, 3H, 5'-CH 3); 1.7 - 1.8 (m, 2H, 2'-CH 2); 2.16 (dd, J = 4.1, 14.7 Hz, 1H, 8ax-H); 2.3-2.6 (m, 6H, CH 2 -N-CH 2, 8eq-H, 3'-H); 3.02 (d, J = 18.8 Hz, 1H, 10ax-H); 3.26 (dd, 1.9, 18.8 Hz, 1H, 10eq-H); 3.46, 3.78 (2 dq, J = 7.0, 9.8 Hz, OCH 2 CH 3; 3.53, 3.93 (2 m, 2H, O-CH 2 CH 2 N); 3.68 (s, 1H, 4'-H), 3.93 (q, J = 6.4 Hz, 1H, 5'-H), 4.08 (S, 3H, OCH 3), 4.56 (dd, J = '2.3 , 4.7 Hz, 1H, OCH (OCH 2 CH 3) CH 2 N), 4.72 (s, 1H, 9-OH), 4.74 (s, 2H, COCH 2 OH), 5.30 (m, 1H, 7-H 5.55 (m, 1H, 1'-H), 7.3 to 8.1 (m, 3H, aromatic Hs), 13.25 (s, 1H, 11-OH), 13.97 (s, 1H, 6-OH).

Example 6 Preparation of 1,5-diiodo-2 (R) -isopropyloxy-3-oxapentane (C3)

The title compound C3 was prepared starting from L-arabinose (3 g) and following the reaction procedure of Examples 1 and 2.

12 97389 1-Isopropyl-p-L-arabinopyranoside (S3), [α] D = + 225 ° (water). 1,5-dihydroxy-2 (R) -isopropyloxy-3-oxa-pentane (E3): TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol (10/1 v / v), Rf = 0.36.

1,5-di (p-toluenesulfonyl) oxy-2 (R) -isopropyloxy-3-oxapentane (F3): TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / acetone (98/2 v / v),

Rf = 0.55.

1 H-NMR (CDCl 3, 200 MHz) δ: 1.05, 1.10 (2 d, J = 6.2 Hz, CH (CH 3) 2); 2.42 (2S, 6H, CH3-TS); 3.64 (2 m, 2H, Ts-O-α 2 O 2 -2 °); 3.76 (m, 1H, CH (CH 3) 2); 3.84 (m, 2H, O-CH-CH2-OTs); 4.08 (t, J = 5.6 Hz, 2H, Ts-Q-CH 2 CH 2 -O); 7.3-7.8 (m, 8H, aromatic Hs).

1,5-diiodo-2 (R) -isopyloxy-3-oxa-pentane (C3): TLC, Kieselgel Plate F254 (Merck), elution system n-hexane / ethyl acetate (10 / 0.5 v / v), Rf = 0.40.

1 H-NMR (CDCl 3, 200 MHz) δ: 1.20, 1.22 (2 d, J = 6.4 Hz, 6H, CH (CH 3) 2); 3.24 (d, J = 5.6 Hz, 2H, O-CH-O 2 -J); 3.28 (t, J = 6.7 Hz, 2H, J-CH 2 CH-O); 3.6 - 3.8 (m, 2H, J-CH 2 CH 2 -O); 3.94 (m, 1H, CH (CH 3) 2); 4.76 (t, J = 5.6 Hz, 1H, O-CH-CHq-J).

Example 7 Preparation of 3'-deamino-3 '- [2 (R) -isopropyloxy-4-morpholinyl] -doxo-rubicin (A3)

Doxorubicin hydrochloride (0.5 g) was reacted with C3 (3 g) following the procedure described in Example 3 to give the title compound A3 ^ (0.21 g) as the hydrochloride salt. TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol (10/1 v / v),

Rf = 0.55. FD-MS: m / e 708 (M &lt; + &gt;).

13 97389 1 H-NMR free base (CDCl 3, 200 MHz) δ: 1.09, 1.16 (2 d, J = 6.0 Hz, CH (CH 3) 2); 1.36 (d, J = 6.6 Hz, 3H, 5'-CH 3); 1.80 (m, 2H, 2'-CH 2); 2.15 (dd, J = 4.0, 14.9 Hz, 1H, 8ax-H); 2.3-2.8 (m, 6H, CH 2 NHCH 2, 8eq-H, 3'-H); 2.97 (d, J = 18.8 Hz, 1H, 10ax-H); 3.26 (dd, J = 18.8 Hz, 1H, 10eq-H); 3.54 (m, 1H, O-CH (H) CH 2 N); 3.74 (s, 1H, 4'-H); 3.81 - 4.1 (m, 3H, OCH (H) CH 2 N, 5'-H, OCH (CH 3) 2); 4.08 (s, 3H, OCH 3); 4.66 (s, 1H, 9-OH); 4.68 (dd, J = 2.2, 4.9 Hz, 1H, OCH [OCH (CH3) 2] CH2N); 4.75 (s, 2H, COCH 2 OH); 5.28 (m, 1 H, 7-H); 5.55 (m, 1H, 1'-H); 7.3-7.8 (m, 3H, aromatic Hs), 13.24 (S, 1H, 11-OH); 13.97 (s, 1H, 6-OH).

Example 8 1,5-Dihydroxy-2 (S) -methoxy-3-oxa-pentane (E4) 1,5-dioxo-2 (S) -methoxy-3-oxa-pentane (D4) (1.5 g, 11 mmol), prepared in "Methods on Carbohydrate Chemistry", Acad. Press., Vol. 1, 445 (1962), was dissolved in a mixture of water (10 ml) and methanol (10 ml) and treated with sodium cyanoborohydride (0.1 g) dissolved in water (2 ml). After 20 minutes, the solution was adjusted to pH 7 with acidic Dowex 50WX2 resin, filtered and the solvent removed under reduced pressure to give 1.4 g (93% yield) of ot-; sikkoyhdistettä. TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol (10/1 v / v), brown spot at Rf = 0.24 after heating the TLC plate sprayed with sulfuric acid.

1 H-NMR (200 MHz, DMSO-d 6) δ: 3.26 (S, 3H, OCH 3); 3.4-3.6 (m, 6H, -CH 2 -CH 2 -O-CH-CH 2 -); 4.37 (t, J = 5.4 Hz, 1H, O-CH-O); 4.40 (broad m, 2H, HO-CH 2 CH 2, CH 2 CH 2 -OH).

14 97389

Example 9 1,5-Di (p-toluenesulfonyl) oxy-2 (S) -methoxy-3-oxa-pentane (F4) 1,5-dihydroxy-2 (S) -methoxy-3-oxa-pentane (E4) (1 , 4 g, 10.3 mmol) prepared as described in Example 8 was dissolved in dry pyridine (10 mL) and treated at 0 ° C with p-toluenesulfonyl chloride (6.4 g, 0.034 mol). The mixture was kept at 4 ° C overnight, then poured into ice-water and finally extracted with methylene chloride. The organic phase was washed with water, separated, dried over anhydrous sodium sulfate and filtered. The solvent was removed under reduced pressure. The crude material was chromatographed on a silica column using methylene chloride as eluent to give 2.8 g (62% yield) of the pure title derivative. TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / acetone (95/5 v / v), brown spot at Rf = 0.55 after heating the TLC plate sprayed with sulfuric acid.

1 H-NMR (200 MHz, CDCl 3) δ: 2.44 (s, 6H, CH 3 -Ph); 3.27 (s, 3H, OCH 3); 3.69 (m, 2H, SO 2 OCH 2 CH 2 -O); 3.90 (m, 2H, SO 2 OCH 2 -CH-O); 4.11 (m, 2H, SO 2 OCH 2 CH 2 -O); 4.56 (t, J = 5.3 Hz, 1H, -O-CH-CH 2); 7.3-7.8 (m, 8H, aromatic; Hs).

Example 10 Preparation of 1,5-diiodo-2 (S) -methoxy-3-oxa-pentane (C4) 1,5-di (p-toluenesulfonyl) oxy-2 (S) -methoxy-3-oxa-pentane (F4) ( 1.6 g, 3.6 mmol) prepared as described in Example 9 was dissolved in methyl ethyl ketone (30 mL) and then treated with sodium iodide (3.04 g, 20.2 mmol) at 85 ° C. for two days. The solvent was then removed in vacuo and n-hexane (50 ml) and water were added to the residue. The organic phase was separated, dried over anhydrous sodium sulfate and filtered. The solvent was removed under reduced pressure to give 1,5-diiodo-2 (S) -methoxy-3-oxa-pentane (C4) (1.2 g, 86% yield). TLC, Kieselgel Plate f254 (Merc®) / elution system methylene chloride, brown spot at Rf = 0.54 after heating the TLC plate sprayed with sulfuric acid.

1 H-NMR (200 MHz, CDCl 3) δ: 3.15 (m, 4H, J-CH 2 CH 2 -OCH-CH 2 -J); 3.40 (S, 3H, OCH 3); 3.80 (m, 2H, J-CH 2 CH 2 -O); 4.62 (t, J = 5.6 Hz, 1H, O-CH-CH2).

Example 11 Preparation of 3'-deamino- [2 "(S) -methoxy-4" -morpholinyl] -doxorubicin (A4)

To a solution of doxorubicin hydrochloride (80 mg, 0.138 mmol) dissolved in dry dimethylformamide (4 mL) was added 1,5-diiodo-2 (S) -methoxy-3-oxapentane (C4, 0.8 g, 2.06 mmol) and triethylamine (0.056 mL, 0.388 mmol). The reaction mixture was kept at room temperature with stirring for 36 hours, then poured into water and extracted with methylene chloride. After performing the standard final steps, the crude product was purified on silica. using a mixture of methyl chloride and methanol (97.5: 2.5 v / v) as the elution system to give 40 mg (yield 45%) of the title compound as the hydrochloride salt after treatment with methanolic anhydrous hydrogen chloride. TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol (19: 1 v / v),

Rf = 0.15.

Free base: 1 H-NMR (400 MHz, CDCl 3) δ: 13.98 (s, 1H, 6-OH); 13.27 (s, 1H, 11-OH); 8.03 (dd, J = 1.1, 7.7 Hz, 1H, 1-H); 7.78 (dd, J = 7.7, 8.6 Hz, 1H, 2-H); 7.39 (dd, J = 1.1, 8.6 Hz, 1H, 3-H); 5.55 (m, 1H, 1'-H); 5.30 (dd, J = 16 97389 2.1, 4.1 Hz, 1H, 7-H); 4.74 (d, J = 4.5 Hz, 14-CH 2 OH); 4.74 (s, 1H, 9-OH); 4.49 (dd, J = 2.6, 4.1 Hz, 1H, NCH 2 -CH (OCH 3) Q); 4.08 (s, 3H, 4-OCH 3); 3.94 (q, J = 6.6 Hz, 1H, 5'-H); 3.93 (m, 1H, NCH 2 CH (H) O); 3.67 (m, 1 H, 4'-H); 3.54 (m, 1H, NCH 2 CH (H) O); 3.38 (S, 3H, NCH 2 CH-OCH 3); 3.27 (dd, J = 19, 18.8 Hz, 1H, 10-Heq); 3.04 (d, J = 18.8 Hz, 1H, 10-Hax); 3.00 (t, J = 4.5 Hz, 1H, CH 2 OH); 2.60 (dd, J = 4.1, 11.4 Hz, 1H, NCH (H) CHOCH 3); 2.6-2.5 (m, 3H, NCH (H) CHOCH 3, NCH 2 CH 2 O); 2.4 - 2.3 (m, 2H, 8-Heq, 3'-H); 2.15 (dd, J = 4.1, 14.7 Hz, 8-Hax); 1.76 (m, 2H, 2'-CH 2); 1.26 (d, J = 6.6 Hz, 3H, 5'-CH 3).

Example 12 Preparation of 1,5-dihydroxy-2 (R) -methoxy-3-oxa-pentane (E5)

The title compound was prepared as described in Example 8 starting from 1,5-dioxo-2 (R) -methoxy-3-oxa-pentane (D5), which in turn can be prepared according to "Methods on Carbohydrate Chemistry", Acad. Press., Vol. 1, 445 (1962). TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol, brown spot at Rf = 0.24 after heating the TLC plate sprayed with sulfuric acid.

Example 13 Preparation of 1,5-di (p-toluenesulfonyl) oxy-2 (R) -methoxy-3-oxapentane (F5) 1,5-dihydroxy-2 (R) -methoxy-3-oxapentane (E5), prepared as described in Example 12 was converted to the title compound F5 following the procedure set forth in Example 9. TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / acetone (95: 5 v / v), brown spot at Rf = 0.55 after heating the TLC plate sprayed with sulfuric acid.

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Example 14 Preparation of 1,5-diiodo-2 (R) -methoxy-3-oxa-pentane (C5) 1,5-di (p-toluenesulfonyl) oxy-2 (R) -methoxy-3-oxa-pentane (F5), prepared as described in Example 13 was converted to the diiodo derivative C5 following the procedure of Example 10. TLC, Kieselgel Plate F254 (Merck), methylene chloride, brown spot at Rf = 0.54 after heating the TLC plate sprayed with sulfuric acid.

Example 15 Preparation of 3'-deamino- [2 "(R) -methoxy-4" -morpholinyl] -doxorubicin (A5)

The title compound was prepared by condensing doxorubicin hydrochloride with 1,5-diiodo-2 (R) -methoxy-3-oxapentane (C5) prepared as described above following the procedure described in Example 1. TLC, Kieselgel Plate F254 (Merck), elution system methylene chloride / methanol (19: 1 v / v), Rf = 0.13.

Free base: 1 H-NMR (400 MHz, CDCl 3) δ: 13.97 (s, 1H, 6-OH); 13.25 (s, 1H, 11-OH); 8.03 (dd, J = 1.1, 7.7 Hz,

. 1H, 1-H); 7.78 (dd, J = 7.6, 7.7 Hz, 1H, 2-H); 7.39 (dd, J

= 1.1, 7.6 Hz, 1H, 3-H); 5.53 (d, J = 3.4 Hz, 1H, 1'-H); 5.29 (dd, J = 2.5, 4.1 Hz, 1H, 7-H); 4.75 (S, 2H, 14_CH 2 OH); 4.71 (s, 1H, 9-OH); 4.46 (dd, J = 2.6, 4.7 Hz, 1H, NCH 2 -CH (OCH 3) O); 4.08 (s, 3H, 4-O); 3.93 (q, J = 6.6 Hz, 1H, 51-H); 3.92 (m, 1H, NCH 2 CH (H) O); 3.70 (m, 1 H, 41-H); 3.56 (m, 1H, NCH 2 CH (H) O); 3.40 (S, 3H, NCT2CH-OO13); 3.26 (dd, J = 19, 19.9 Hz, 1H, 10-Heq); 3.03 (d, J = 19.9 Hz, 1H, 10-Hax); 2.66 (dd, J = 2.6, 11.4 Hz, 1H, NCH (H) CHOCH3); 2.53 (m, 1H, NCH (H) CH 2 O); 2.5-2.3 (m, 4H, NCT (H) CH 2 O, NCH (H) CHOCH 3, 8-Heq, 3'-H); 2.15 (dd, J = 4.1, 14.7 Hz, 8-Hax); 1.8-1.7 (m, 2H, 2'-CH 2); 1.36 (d, J = 6.6 Hz, 3H, 5'-CH 3).

18 97389 Biological activity of 31-deamino- [2 ”(S) -methoxy-4" -morpholinyl] -doxorubiclin (A4) and 31-deamino-f2 "(R) -methoxy-4" -morpholinyl-doxorublin (A5)

The compounds have been tested in several experimental systems to confirm their cytotoxicity and antitumor activity in experimental animals compared to the original docorubicin. The new anthracyclines are more cytotoxic than the parent drug on LoVo and LoVo doxorubicin-resistant cell lines (LoVo / Dx) (Table 1) and are active in vivo on doxorubicin-resistant cell lines.

Primary in vivo analysis was performed on BDF1 mice with P388 doxorubicin-resistant Johnson leukemia (P388 / Dx) (105 cells / mouse). The drugs were administered i.v. l. the day after tumor inoculation. The results are shown in Table 2. Both compounds were active and more potent than doxorubicin.

Compound A4 has also been tested for doxorubicin-resistant P388 Schabel in vitro (Table 3) and in vivo in BDF1 mice (105 cells / mouse), treatment i.v. On day 1 after tumor inoculation. Finally, compound 1a is. studied in a solid tumor such as mouse and human mammalian carcinoma (MX1) i.v. and orally (Tables 5 and 6).

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table 1

Colony assay for LoVo and LoVo / Dx resistant cells in vitro (duration of treatment 4 hours)

Compound LoVo Lovo / Dx RIb (IC50 = ng / ml) a (IC50 = ng / ml) a doxorubicin 48.8 2553 52.6 A4 8.7 31.7 3.6 A5 6.5 40.1 6.1 a) IC50 = concentration that inhibits 50% of colony growth b) R1 = resistance index = (IC50 Lovo / Dx) / (IC50 LoVo)

Table 2 Effect of A4 and A5 on doxorubicin-resistant P388 Johnson leukemia in vivo

Compound O.D.c T / C ^ _ (mq / kq) _% _ doxorubicin 13 86 A4 0.09 250 A5 0.13 244 c) O.D. = optimal dose: maximum tolerated dose d) T / C% = median survival time of treated mice compared to median survival time of controls x 100.

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Table 3 Effect of A4 on sensitive and doxorubicin-resistant P388 leukemia (Schabel) in vitro (treatment 1 h)

compound P388 P388 / DX

(IC50 = ng / ml) c (IC50 = ng / ml) c doxorubicin 52.7 4000 A4 7.6 24.3 c) IC50 = concentration that inhibits 50% of cell survival

Table 4 Effect of A4 on doxorubicin-resistant P388 Schabel leukemia in vivo

Compound O.D.c T / C ^ _ (mq / kq) _% _ doxorubicin 13 100 A4 0.09 153 li 21 97389

Table 5 Effect of A4 on mouse mammalian carcinoma

Compound Method and Treatment- O.D.c. Tumor _schedule_ (mg / kg)% inhibition of doxorubicin i.v. q4dx4f 5.85 99 A4 i.v. q4dx4 0.065 94 p.o. q4dx4 ^ 0.1 97 f) i.v. q4dx4 = processing i.v. every 4 days 4 times g) p.o. q4dx4 = oral treatment every 4 days 4 times

Table 6 Effect of A4 on human mammalian carcinoma (MX1)

Compound Method and Treatment- O.D.c Tumor _schedule_ (mq / kq) lnhibointl-% doxorubicin i.v. q7dx3 ^ 6 72 A4 i.v. q7dx3 0.05 98 p.o. q7dx3i 0.13 99 h) i.v. q7dx3 = processing i.v. every 7 days 3 times. i) p.o. q7dx3 = oral treatment every 7 days 3 times

Claims (9)

A process for the preparation of an anthracyclic glycoside of the general formula A OCH 3 O H 4 O = 27 h <t ν% ί A or its pharmaceutically acceptable salt, wherein Formula X represents a linear or branched C benzyl group and having (S) or (R) configuration at the carbon atom 2 ", characterized in that (i) doxorubicin or its acid addition salt is reacted with a diode compound of formula C c * wherein the residue X is as defined above, and (ii) if desired, the anthracycline glycoside of formula A thus obtained is converted to its pharmaceutically acceptable acid dithio salt. Process according to claim 1, characterized in that the doxorubicin or its hydrochloride, diluted in a polar aprotic solvent, is reacted at room temperature and in the presence of a dry organic base with a diode compound of the general formula C, wherein a corresponding morpholinyl doxorubicin derivative having Formula A is obtained, which derivative is purified in a silica column using methylene chloride-methanol (97/5 v / v) elution system and then isolated as its hydrochloride by treatment with methanolic anhydrous hydrogen chloride. Process according to claim 1 or 2, characterized in that X is methyl in the compound of formula C. 4. A process according to claim 1 or 2, characterized in that X is C 2 -C 4 alkyl in the compound of formula C. Process according to any of the preceding claims, characterized in that 3'-deamino-3 '"[2" (S) -benzyloxy-4 "-morpholinyl] -doxorubicin and its hydrochloride, 3'-deamino-3'- [2 "(S) -ethoxy-4M-morpholinyl] -doxorubicin and its hydrochloride or 3'-deamino-3 '- [2" (S) -methoxy-4 "-morpholinyl] -doxorubicin and its hydrochloride are prepared. 6. A diode compound of formula C XX, c wherein X represents a linear or branched C 1 -C 3 alkyl group or benzyl group. 7. A process for preparing a diode compound of formula c wherein X represents a linear or branched C 1 -C 3 alkyl group or benzyl group, characterized in that (a) a compound of formula S (b) the thus obtained dialdehyde derivative of formula D1 wherein the residue X is as defined above is reduced, (c) the dihydroxy derivative of formula E1 HO H wherein the residue X is as defined above is sulfonated, and (d) the sulfonated derivative thus obtained is added. II »· 97389 8. A process according to claim 7, characterized in that D or L-arabinose is reacted with the alcohol X-OH, wherein the residue X is as defined in claim 7, whereby a compound of formula S1 is formed. A process according to claim 7, characterized in that the dihydroxy derivative of formula E1 is reacted with p-toluenesulfonyl chloride in step (c).